package com.gzx.spring.boot.utils;

import java.lang.reflect.Field;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.aop.framework.AdvisedSupport;
import org.springframework.aop.framework.AopProxy;
import org.springframework.aop.support.AopUtils;
import org.springframework.util.ClassUtils;

/**
 * 根据bean对象，获取真正实例
 * 
 * @author wuyan_dxm
 * 
 */
public class AopTargetUtils {
    private static Logger LOGGER = LoggerFactory.getLogger(AopTargetUtils.class);

    /**
     * 获取 目标对象
     * 
     * @param proxy 代理对象
     ** @return
     ** @throws Exception
     */
    public static Object getTarget(Object proxy) throws Exception {
        if (!AopUtils.isAopProxy(proxy)) {
            return proxy;// 不是代理对象
        }

        if (AopUtils.isJdkDynamicProxy(proxy)) {
            if (LOGGER.isDebugEnabled()) {
                LOGGER.debug("is JdkDynamicProxy,className:{}", proxy.getClass().getName());
            }
            return getJdkDynamicProxyTargetObject(proxy);
        } else { // cglib
            if (LOGGER.isDebugEnabled()) {
                LOGGER.debug("is CglibProxyTargetObject,className:{}", proxy.getClass().getName());
            }
            return getCglibProxyTargetObject(proxy);
        }
    }

    @SuppressWarnings("deprecation")
	public static Class<?> getRealClass(Object proxy) {
        if (ClassUtils.isCglibProxy(proxy)) {
            return proxy.getClass().getSuperclass();
        } else {
            return proxy.getClass();
        }
    }

    public static Object getCglibProxyTargetObject(Object proxy) throws Exception {
        Field h = proxy.getClass().getDeclaredField("CGLIB$CALLBACK_0");
        h.setAccessible(true);
        Object dynamicAdvisedInterceptor = h.get(proxy);
        try {
            Field advised = dynamicAdvisedInterceptor.getClass().getDeclaredField("advised");
            advised.setAccessible(true);
            Object target = ((AdvisedSupport) advised.get(dynamicAdvisedInterceptor)).getTargetSource().getTarget();
            return target;
        } catch (Exception e) {
            return proxy;
        }
    }

    private static Object getJdkDynamicProxyTargetObject(Object proxy) throws Exception {
        Field h = proxy.getClass().getSuperclass().getDeclaredField("h");
        h.setAccessible(true);
        AopProxy aopProxy = (AopProxy) h.get(proxy);
        Field advised = aopProxy.getClass().getDeclaredField("advised");
        advised.setAccessible(true);
        Object target = ((AdvisedSupport) advised.get(aopProxy)).getTargetSource().getTarget();
        return target;
    }
}
